


Blame It All On Human Nature

by deathishauntedbyhumans



Category: The Umbrella Academy (TV)
Genre: Emotional Constipation, Emotional Hurt/Comfort, Love Confessions, M/M, POV Diego Hargreeves, Pseudo-Incest, Sexual Humor, Wordcount: 1.000-3.000, no beta we die like ben
Language: English
Status: Completed
Published: 2019-08-26
Updated: 2019-08-26
Packaged: 2020-09-27 12:27:51
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,881
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20407753
Author URL: https://archiveofourown.org/users/deathishauntedbyhumans/pseuds/deathishauntedbyhumans
Summary: Diego has feelings for Klaus. Klaus has feelings for Diego. This should be easy, right? (Wrong, Five says, with his typical bored air about him.)





	Blame It All On Human Nature

**Author's Note:**

> Title (and inspiration for the fic!!) comes from Coin’s _Talk Too Much_. 
> 
> Takes place after the whole Apocalypse/Not-pocalypse thing in some timeline where everyone is good and happy and getting better.

_ You know I talk too much _

_ Honey come put your lips on mine _

_ And shut me up _

_ We can blame it all on human nature _

* * *

This _ thing _with Klaus has been going on for three weeks, now. 

Diego doesn’t know if he’s bragging or complaining when the thought pops into his head, but he sure as hell wishes he could pick a feeling and stick with it. Confusion, lust, resentment, fondness… It’s all boiled down into one convoluted mess of chemicals clogging up his brain and making him slower. He’s jumpier than usual, and he snaps at anyone who so much as glances in his direction, because it’s all _ too much. _

Klaus, damn him, has succeeded in doing what he does best: Stealing his way into Diego’s heart like the goddamn thief that he is and making the biggest mess he possibly can. 

“—but what’s really important are the _ fangs,” _Klaus rambles, obviously unaware that Diego stopped listening to him nearly a half hour prior. “Not only for the sex appeal, mind you, but also—“

Frolicking around in a neon tank top and booty shorts that are too tight for him, Klaus is an absolute sight to behold (as though his usual faux-chipper demeanour isn’t enough to hold Diego’s attention). _ Especially _ because he’s wearing that ridiculous army-green vest on top of the highlighter of a pink shirt. It _ should _ look atrocious. On anyone else, Diego would make a subtle call to the authorities and have the offending asshole arrested on crimes going against the very laws of nature. (And general wearability and style. Who says the fashion police aren’t real?) But on Klaus, it _ works, _and it’s both infuriating and smoking hot all in the same stroke. 

Diego doesn’t know whether he wants to smack Klaus, or fuck him. 

Although, this _ is _Klaus, so doing both really isn’t out of the question. 

“—iego, c’mon, man.” Diego blinks. Klaus’ hand is an inch from his face, finger snapping insistently. “Come back from whence you came,” he adds in a spooky voice, throwing it down a few octaves. 

Against his will, an amused smirk twitches at the corners of Diego’s lips. “Alright, alright, I’m with you, Séance,” he says, and Klaus puts on a pout that _ should _look stupid on a grown man, but manages to somehow only look cute instead. 

“Were you even listening to me.”

Diego racks his brain. “Uh… Fangs?” he supplies in an attempt to seem like he’d actually been invested in Klaus’ nonsensical rambling. “And sex appeal?” He pauses, trying to put two and two together while Klaus pokes his lower lip out further and bats his lashes in what Diego assumes is supposed to be sadness. (It looks like he’s got something in his eye, but Diego has learned to pick his battles a _ little _more wisely since he and his siblings parted ways the first time, so he says nothing about it.) “Vampires?”

With a disgruntled huff, Klaus flounces over to Diego and unceremoniously barrels his way right into Diego’s lap. Diego goes stiff at the contact, surprised as always despite himself at the way Klaus manages to dissolve the walls Diego builds around himself so easily.

“Lucky guess,” Klaus mutters. He slides his hands up Diego’s back and nestles himself close, tucking his head into the space between Diego’s neck and his shoulder. “You’re all tense, Di.”

“Shut up.” Diego simultaneously wants to pull Klaus closer and shove him down onto the floor. 

Klaus seems to sense it, because the next thing Diego knows, Klaus is licking a stripe from his collarbone to his ear and then biting down on his earlobe. “I know something’s eating you, and it’s _ not _me,” he murmurs. “C’mon, bro. What’s got your vigilante-panties in a bunch?”

On any other day, where Diego was feeling more horny and less on-edge, he might have taken the bait Klaus was obviously putting out. In an instant, though, his roiling emotions catch up with him, and Klaus lands ass-first on the floor before Diego even knows what he’s doing. 

Klaus stares up at him in shock. “Diego, what the _ fuck—?” _

“I need to go on patrol,” Diego lies easily, pushing himself off the bed. “Don’t wait up for me.” Without a backwards glance, he slides out of the room. 

If he pretends he doesn’t see Klaus’ hurt look, maybe his chest won’t constrict and his heart won’t ache. 

* * *

He doesn’t go on patrol. 

It’s far too early and far too light out for vigilante work, and Diego’s lack of concentration isn’t exactly helping his case. Instead of leaving the house, he sneaks his way up to the attic, where he’s hung a couple of punching bags and brought in some of the shitty equipment his gym was planning on tossing. 

It’s not state-of-the-art, but it works in a pinch, and Diego is… definitely in a pinch, at the moment. 

He busies himself with training, with throwing knives and beating the shit out of the bags. When he throws himself into his work, he can almost pretend that there’s no emotional turmoil broiling in his chest and churning in his stomach. It’s easier this way, to not think about Klaus’ pout, his hands, his hair, his dick. 

And then he turns around to throw another knife and narrowly avoids hitting Five in the process, curving the blade at the last moment to keep it from sinking into his flesh. Five doesn’t even flinch. 

“_Jesus Chri—“ _

“You’re avoiding Number Four,” Five says plainly, crossing his arms over his chest. Diego feels, _ bizarrely_, like he’s being scolded by a strange mix of their father and some random child off of the street. 

Diego stalks past Five to retrieve his knife. “Don’t sneak up on me when I’m training,” he retorts, ignoring the jibe. He pulls the knife free of the wooden beam it had stuck itself into upon curving away from Five. 

Five snorts. “You don’t get it, do you?” he says, trailing behind Diego. When Diego turns, Five is uncomfortably close to him, peering at him with a slanted gaze that looks unsettlingly _ old _on Five’s young babyface. 

“There’s nothing to get,” Diego responds, more harshly than he means to. He wants to flinch, but he doesn’t get a chance before Five scoffs and reaches for the knife in his hands. 

“Don’t give me that bullshit, Diego. We both know you’re talking out of your ass.” And Diego blinks and lets Five take the knife, because that sentence coming out of _ that _mouth? It’s always too much to hear. “Klaus is in love with you, you idiot.”

Diego’s jaw drops. His mouth actually falls open, shock painting itself over his features like a Bob Ross special feature. “_ What?” _

Five turns the knife over in his fingers. “Sure, you two haven’t been as obvious as Allison and Luther, but do you _ really _think you’ve been subtle? We all have to live with each other. None of us are blind… Well, barring Luther, maybe, but he’s part monkey, so he doesn’t actually count.”

Diego doesn’t even _ want _to wrap his head around the weird implications of that sentence. “Hang on, go back. You think Klaus is in love with me?”

“I don’t _ think, _ Diego. I _ know.” _ Five rolls his eyes. “You’ve been up here for the past—“ He checks the watch on his wrist. “—three and a half hours, thudding around and throwing things like the testosterone-filled mess that you are. Klaus has been moping around downstairs for the same amount of time, moaning and groaning about how you hate him to anyone who will listen. Obviously, we both know that _ that _is a complete and total lie, but Allison and Luther can barely handle their own emotional constipation and Vanya is busy training with Pogo, so I figured it was up to me to kindly ask you to stop being so difficult and deal with him before one of us winds up killing him ourselves.” Five looks up and offers his usual cursory smile, the one that only resides on his lips and doesn’t spread to his eyes. “You should close your mouth, Number Two. You’ll catch flies like that.” He offers Diego the knife back, his fingers gingerly pinching the blade. 

It’s all Diego can do to accept the hilt of the weapon, and as soon as it’s settled in his hand, Five takes a step backwards and melts out of the room. 

* * *

Klaus is lounging atop the kitchen table when Diego finally gathers his wits about him enough to leave the attic again. Five’s little rant leaves him more shaken than he’d like to admit, but… He also has to concede that the little shit has a point. 

If Klaus is really in love with him, Diego’s going to handle it. 

_ Really_. He is. 

“Thought you were going out on patrol,” Klaus says when he catches Diego’s eye. He’s viewing him upside-down, with his head lolling off the edge of the table carelessly. A forced calm emanates from his voice; if Diego was a lesser man, he might’ve winced. 

Instead, he shrugs off the guilt threatening to overcome him from his decision to blow Klaus off earlier and steps further into the room. “I decided not to,” he states plainly. It’s not a _ lie _. He’d never intended to go out on patrol in the first place, either, but Klaus doesn’t need to be privy to that particular bit of sensitive information. “What are you doing?”

Klaus laughs, a harsh sound that’s too loud and fake in the otherwise-quiet room. “Oh, _ now _ you care?” He snorts. “You can fuck right off, Diego-me-boy. I’m not doing anything _ illegal, _ and I’m not doing any _ drugs, _so it’s not like it matters to you what I’m doing.”

Without thinking, Diego crosses the rest of the way to the table, rounding it so that Klaus is forced to look straight at him instead of upside-down. “Klaus, don’t—“

“Ah!” Klaus rolls over smoothly, his ass just barely avoiding falling out from beneath his shorts. Diego does his best to pretend he doesn’t notice. “The famous ‘Klaus, don’t!’ We just _ love _ that line around here, don’t we? ‘Klaus, don’t do drugs’,” he starts, pitching his voice up an octave and clasping his hands together near his face. “‘Klaus, don’t sit there.’ ‘Klaus, don’t say that.’ ‘Klaus, don’t be such a piece of _ shit’.” _ His voice drops back to normal on the word _ shit, _and his face falls from the faux-angelic expression he’d been wearing into something much darker. “Which one is it today, hm?”

“Knock it off.” Diego’s voice is hard, and his fingers are itching to grab Klaus, to shake him until he stops this ridiculous game, to shove him off the table so he’ll quit pretending he doesn’t know what’s going on. He’s well-aware that violence won’t solve their problems, but it’s _ so _much easier than talking. Which, speaking of… “Can you just— Can we talk?”

Klaus sits up. “We _ are _talking,” he points out loftily. Diego wants to… punch him, maybe. Or kiss that arched look right off his smug-ass face; he’s not particular about which comes first. 

Diego takes a deep breath. “Not here,” he says. He gestures stiffly towards the hall. “Come up to my room?”

For the first time since he’d entered the room, Diego registers a flicker of fear flicker across Klaus’ face. It’s gone as quickly as it appears, but Diego is as certain as he can be that it had been there. He’s learned to trust his senses over the years, and right now, they’re telling him that —despite everything in him buzzing nervously otherwise— he needs to proceed with caution, or risk frightening Klaus off even further. 

“Please?” 

Klaus slides off the table, the action smooth despite the new tension Diego spots in his shoulders. “Yeah, yeah, fine. Whatever.”

Again, Diego _ aches _with the urge to reach out as Klaus brushes past him, his fingers twitching at his sides. Klaus doesn’t look at him as he steps through the doorway, but Diego can’t keep his own gaze from following him as he follows. They make their way up the stairs in silence. 

It’s a funeral procession without a funeral, but Diego doesn’t know how to change that without fucking everything up further, so he says nothing at all until the door to his room is firmly shut behind him. 

“You’ve got me here.” Klaus states the obvious with a careful edge to his tone that Diego doesn’t like, flopping carelessly down onto Diego’s bed. His mattress is hard and he _ knows _it, but Klaus lounges there like the shitty box-spring was tailor-made to cup his ass. 

Diego double-checks that the door is locked, and then slowly makes his way to the bed so he can sit on the end of it. “Five, uh— Five said you were pretty upset, after I… left, earlier.” _ Smooth, Diego. Really fucking smooth. _

Klaus looked like he was chewing on the inside of his cheek. “It was whatever. You had to go on patrol.” 

Diego is pretty damn certain they _ both _know he was lying. 

This game that Klaus is playing, the game that Diego has _ let _ him play, and played along with? It grates and it grates at him, and Diego has to take a deep breath and focus on visualising the words he wants to say because he’s _ done. _

If Klaus started it, then Diego is ending it, and he’s determined to actually do something _ right _ with them, for once _ . _

“I’m in love with you,” Diego says evenly, and Klaus jolts upright like he’s been electrocuted. 

For a long, long moment, they stare at each other. Klaus is finally looking at him again, and the depth of emotion in his eyes makes Diego’s breath catch in his throat. He’s never felt like he was about to drown as much as he does in this moment, with Klaus’ gaze threatening to pull him under completely. 

“Say that again,” Klaus demands finally, his voice cracking. 

Diego doesn’t hesitate. “I’m in love with you,” he repeats. He can see the words when he blinks; they’re etched into the blackness of his eyelids in a neon pink script that looks remarkably like the jagged, pointed handwriting Klaus is known for among the siblings. _ Envision the words in your mind, _Grace’s voice murmurs in the back of his head. 

Even if he wanted to, Diego didn’t think he could envision anything else in this moment.

Without warning, Klaus launches himself across the remaining expanse between them. Diego catches him with a grunt, easily pulling him in closer. When he wraps his arms around Klaus, he can feel him shaking. 

It’s a little easier to think, now that the biggest elephant in the room has been acknowledged. Diego lets Klaus tuck his face away against his neck, lets him shudder in his arms, and presses a kiss to the side of his head. “I’m sorry,” he murmurs. “I’m sorry for being… the way I get. I’ve always been shitty at feeling things, but you—“ He slides his fingers into Klaus’ hair, brushing it away from his forehead. “You make me _ feel,” _he says, mumbling the words against Klaus’ skin. “And sometimes I want to curse you out for it, but damn you, I love you even when I want to kill you.” 

“You couldn’t kill me. I’m a bad bitch,” Klaus mumbles, but it’s a weak attempt at a joke, especially coupled with the fact that the statements ends in a sob. Diego holds him tighter. 

“I _ wouldn’t,” _he replies fiercely. 

Slowly, Klaus’ trembling subsides, leaving him curled up tightly in Diego’s lap. Diego brushes his lips behind the shell of his ear. 

“You’re so tense,” he murmurs with the ghost of a smile on his face. 

He can feel Klaus smile against his neck. “You stole my line,” he mumbles. Carefully, Klaus leans back, and Diego can see his eyeliner smudging around his eyes. “For what it’s worth,” he says softly, the smile fading some. “I love— I’m _ in _love with you, too.” 

Despite Five’s reassurance, despite the fact that Diego had already _ put it together _on his own (and that it had caused him so much grief until he’d gotten his own head out of his ass), hearing the words straight from Klaus himself shoves a weight off of his shoulders that Diego hadn’t even realised he’d been carrying with him. 

A smile, soft and genuine, stretches over his features before he can even begin to think about checking it. Klaus makes a soft, desperate noise in the back of his throat and surges forward, kissing Diego soundly and finally melting into him. 

Somewhere in his head, behind the heady focus on Klaus and the _ magnificent _ things he’s doing with his tongue, Diego makes a mental note to thank Five later; even if he hadn’t had much _ tact _on the matter, the kid’s interference is definitely appreciated. 

And then, Klaus pushes him down onto the bed and all but slithers up on top of him, and Diego loses his ability to compartmentalise thought entirely. All he can think about is _ Klaus_, and for the first time in days —in _ months, _ in _ years— _he doesn’t mind it at all. 

**Author's Note:**

> This fic evolved into So Much more than I originally planned? Five wasn’t even supposed to _be_ in it!! And yet, here we are, and there he is. 
> 
> <s>Yes, Klaus referenced a vine. The apocalypse happens in 2019 so you cannot tell me that Klaus didn’t get high off his ass and watch vine comps all thru the Golden Era™. Sorry lads I don’t make the rules I just face the facts.</s>
> 
> Kudos/comments are love!! Come scream at me on tumblr @deathishauntedbyhumans.


End file.
